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1.
Nano Lett ; 20(12): 8615-8619, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33238104

RESUMO

Here, we report on ultrafast all-optical modulation of the surface-plasmon (SP)-assisted transverse magneto-optical Kerr effect (TMOKE) and the reflectance in a one-dimensional nickel magnetoplasmonic crystal (MPC). A 50 fs nonresonant laser pump pulse with 7 mJ/cm2 fluence reduces the magnetization by 65%, which results in the suppression of TMOKE in the SP-resonant probe from 1.15% to 0.4%. The differential reflectance of SP-resonant probe achieves 5.5%. Besides this, it is shown that electron thermalization and relaxation in MPC are several times slower than those in the plane nickel.

2.
Adv Gerontol ; 34(1): 144-151, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33993675

RESUMO

In order to identify the relationship between mental and physical disorders in the elderly and senile age, 70 patients were examined in one of the clinics in Arkhangelsk, including 56 (80%) persons aged 60-74 years and 14 (20%) people aged 75 years and older. A questionnaire was conducted, data from outpatient records were studied, and the clinical status assessment was used, as well as methods for determining mental and physical condition. The most frequent mental and physical disorders were the cognitive and depressive disorders presence, a high risk of malnutrition syndrome, sarcopenia and falls syndrome, reduced functional capabilities, while senile patients had significantly more pronounced disorders. It has been shown that the cognitive and depressive disorders presence in the elderly and senile increases the falling syndrome risk and reduced functional capabilities, and in old age - sarcopenia syndrome.


Assuntos
Sarcopenia , Acidentes por Quedas , Idoso , Humanos , Inquéritos e Questionários
3.
Angiol Sosud Khir ; 27(4): 59-69, 2021.
Artigo em Russo | MEDLINE | ID: mdl-35050250

RESUMO

AIM: The study was aimed at assessing efficacy and safety of endovascular treatment of abdominal aortic aneurysms based on 11-year experience with implantation of stent grafts. PATIENTS AND METHODS: We retrospectively analysed outcomes of treatment of 242 patients with abdominal aortic aneurysm during the period from 2008 to 2019. Of these, 210 (86.78%) were males, mean age 69.32±7.36 years. Diagnosis was made using colour duplex scanning and contrast-enhanced multislice spiral computed tomography, with implanting the following stent grafts: Ella - 44, Ovation Prime - 33, Anaconda - 13, Endurand - 77, Aortix - 2, Zenith - 33, Seal - 39, with one endoprosthesis placement failed. Assessing safety of the operation, we took into consideration lethality due to aortic rupture/thrombosis. Efficacy was taken to mean technical success of the operation (implantation of all components of the endograft without switch to open surgery), the number of reoperations. RESULTS: Technical success of the operation was achieved in 98.35% of cases. In 1 case due to pronounced arterial calcification for technical reasons we failed to position the stent graft and in another case - the contralateral leg of the Ella prosthesis. The early postoperative period revealed: type A1 endoleak - 3.7%, type IB - 4.13%, type IIA - 6.6%, type IIB - 4.54%, type III - 0.83%, type IV - 0.83%. Repeat operations were performed in 20 (8.2%) patients within 30 days after the intervention and in 32 (13.22%) in the remote period. In the early postoperative period two conversions were performed: 1) iliorenal bypass grafting for restoration of blood flow through the renal artery occluded by endoprosthesis wall; 2) evacuation of retroperitoneal haematoma due to rupture of the common femoral artery. Lethality during the whole period of follow up amounted to 32 (13.22%) cases. Of these, due to aortic complications 4.54% (n=11) and due to accompanying pathology 8.67% (n=21). A direct correlation was revealed between the aortic diameter and duration of the operation which in turn increases the risk of complications requiring re-operation or resulting in a lethal outcome (RR - 1; 95% CD 1- 1; p=0.026). CONCLUSION: Our experience showed high safety and efficacy of stent graft implantation in treatment of patients with abdominal aortic aneurysms and high surgical risk.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Idoso , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Stents , Resultado do Tratamento
4.
J Acoust Soc Am ; 145(6): 3578, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31255112

RESUMO

In a beluga whale, the positions of sound receiving areas on the head surface were determined by comparing the acoustic delays from different sound source positions. For this investigation, auditory evoked potentials (AEPs) in response to short tone pips were recorded. Latencies of the first AEP wave that presumably reflected the activity of the auditory nerve were measured at different sound source azimuths. For AEPs of equal amplitudes, the difference in AEP latencies was attributed to the difference in the acoustic delays. These delay differences were used to compute the azimuths of sound receiving points. Measurements were conducted at frequencies from 22.5 to 90 kHz in half-octave steps. At all stimulus frequencies, the receiving points were located 24-38 cm caudal of the melon tip, which is near a proximal part of the lower jaw. Thus, the results indicated the latero-mandibular acoustic window. Possible causes for not finding a lateral or ventro-mandibular window are discussed.


Assuntos
Percepção Auditiva/fisiologia , Beluga/fisiologia , Potenciais Evocados Auditivos/fisiologia , Audição/fisiologia , Estimulação Acústica/métodos , Acústica , Animais , Limiar Auditivo/fisiologia , Nervo Coclear/fisiologia , Humanos , Som
5.
Artigo em Russo | MEDLINE | ID: mdl-31884754

RESUMO

The organization of out-patient care of elderly people has its own clinical and organizational characteristics. The study was carried out to establish quality factors of ambulatory polyclinic medical care of elderly people from the position of attending physician. The sampling consisted of 80 physicians interviewed. Out of them 70 were females (87.5%), 50 local therapists and general practitioners and 30 physicians of various specialties. The genuinely elaborated questionnaire was applied. Results and discussion. It is established that most physicians are aware of the need of improving quality of medical care of elderly patients and developing geriatric care. The percentage of elderly patients in ambulatory polyclinic network makes up to 50%, and in particular cases up to 60-70%. The majority of elderly patients visit their physician 1-2 times per month. More than 50% of physicians consider elderly patients have to be observed by physicians of geriatric profile that confirms actual need in this medical specialty. The social and organizational factors of quality of medical care are identified: insufficient duration of physician admission, low level of preferential medications support, lacking of cash resources in patients to purchase prescribed medications, difficulties in making an appointment to medical specialist and district physician, difficult access of medical organization. The orientation of doctors in provision of care to elderly patients only to medication therapy is established. Conclusion. The specific characteristics of identified factors of quality of medical care of elderly patients are to be considered in developing directions of optimizing medical care for this contingent.


Assuntos
Assistência Ambulatorial , Medicina , Médicos , Idoso , Instituições de Assistência Ambulatorial , Feminino , Humanos , Pacientes Ambulatoriais
6.
Dokl Biol Sci ; 478(1): 1-4, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29536396

RESUMO

The spectrum contrast threshold for the comb-filtered signal was measured at various ripple densities in listeners with normal hearing. The lowest spectrum contrast thresholds of less than 0.1 appeared at a ripple density of 3-4 oct-1. With the ripple density falling down to 1 oct-1, the threshold increased to 0.17. At the ripple density higher than 4 oct-1, the threshold was also growing to achieve 1.0 at a density of 7-8 oct-1. An increase of threshold at high ripple densities can be explained by integration within critical bands. At low ripple densities, the threshold increase may be a result of the lateral suppression that led to sharpening of the spectral contrast.


Assuntos
Percepção Auditiva , Estimulação Acústica , Vias Auditivas/fisiologia , Humanos , Limiar Sensorial
7.
Dokl Biol Sci ; 481(1): 135-138, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30171465

RESUMO

The frequency resolving power of hearing (FRP) of the beluga whale Delphinapterus leucas was studied as dependent on influence of lasting low-intensity sounds (of the ultrasonic range from -20 to +10 dB). Testing of the spectrum ripple-phase reversal was used in conjunction with a noninvasive recording of auditory evoked potentials. FRP parameters were found to depend nonmonotonically on the intensity of the background noise. The resultant adaptation effects can be explained by the fact that, in response to the high-intensity signals, the auditory system sensitivity is reduced to the level optimal for analysis of these signals.


Assuntos
Beluga/fisiologia , Ruído , Estimulação Acústica , Animais , Potenciais Evocados Auditivos/fisiologia
8.
Adv Gerontol ; 30(3): 442-449, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28849892

RESUMO

To develop algorithm of diagnostics of cognitive and affective disorders in elderly and senile age 98 representatives of this age group were examined (1st group - 68 persons 60-74 years, 2nd group - 30 patients older than 75 years). For the diagnosis of cognitive disorders the developed and adapted «Short rating scale of cognitive functions¼, to diagnose emotional disorders - «Ðospital scale of anxiety and depression HADS¼ were used. Cognitive impairment was revealed in 39,8% of the elderly (1st group - 28,7% in 2nd group - 61,6%). Affective disorders 51,6% of respondents had; however, signs of anxiety - 40,9% and depression - 27,7%. Algorithm for the diagnosis of cognitive and emotional disorders in elderly and senile age, comprising the steps of: screening and diagnostic, clinical and pathopsychological, laboratory and instrumental diagnostic, psychodiagnostic, can be recommended for use in general medical practice (therapists, general practitioners, geriatrics) for an earlier secondary prevention and, if necessary, early correction of mental health disorders.


Assuntos
Algoritmos , Transtornos de Ansiedade/diagnóstico , Transtornos Cognitivos/diagnóstico , Transtorno Depressivo/diagnóstico , Idoso , Humanos , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica
9.
Adv Gerontol ; 29(1): 141-153, 2016.
Artigo em Russo | MEDLINE | ID: mdl-28423260

RESUMO

The article describes the structure of criteria of severity and recommendations for the diagnosis of emotional sphere disorders in elderly. An algorithm for diagnosis of emotional sphere is described, which includes four phases: screening and diagnostic, clinical and patho-psychological, laboratory and instrumental diagnostic, psycho-diagnostic; it can be applied as to estimate the prevalence of various forms of emotional disorders, and for their early correction and prevention at the individual level. The criteria of anxiety expression evaluation and asthenic disorders are presented. The recommendations can be used in the activities of somatic practices doctors (therapist, general practitioners, neurologists).


Assuntos
Ansiedade , Idoso , Transtornos de Ansiedade , Humanos , Prevalência
10.
Klin Med (Mosk) ; 93(7): 71-7, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26596064

RESUMO

A case of primary infectious endocarditis with the lesion of mitral valve in a pregnant woman is reported The diseases was caused by meticillin-resistant Staphylococcus aureus. Special attention is given to inefficiency of beta-lactame antibiotics against this infection and beneficial effect of daptomycin therapy. This observation confirms literature data about high frequency of thromboembolic complications of S aureus-induced infectious endocarditis due to the production of various coagulases and von Willebrand factor-binding protein by these microorganisms. An increase of coagulation caused by S. aureus is mediated through activation of prothrombin, factor XIII, and fibrin-binding fibronectin. It requires prescription of direct thrombin inhibitor pradax that proved to yield good results in the treatment of our patient. It is concluded that infectious endocarditis in pregnant women is characterized by an atypical clinical picture due to impaired immunity associated with rapid progression of the process after delivery, high frequency of thromboembolic and DIC syndromes.


Assuntos
Dabigatrana/administração & dosagem , Daptomicina/administração & dosagem , Endocardite Bacteriana , Staphylococcus aureus Resistente à Meticilina , Valva Mitral , Complicações Cardiovasculares na Gravidez , Tromboembolia Venosa , Adulto , Antibacterianos/administração & dosagem , Antitrombinas/administração & dosagem , Ecocardiografia/métodos , Endocardite Bacteriana/complicações , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/microbiologia , Endocardite Bacteriana/fisiopatologia , Feminino , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Valva Mitral/diagnóstico por imagem , Valva Mitral/patologia , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Complicações Cardiovasculares na Gravidez/microbiologia , Complicações Cardiovasculares na Gravidez/fisiopatologia , Resultado da Gravidez , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/fisiopatologia
12.
Klin Khir ; (7): 34-5, 2014 Jul.
Artigo em Russo | MEDLINE | ID: mdl-25252410

RESUMO

The results of treatment of 334 patients in the clinic in 1984 - 2013 yrs period were analyzed, who suffered mitral valve stenosis, complicated by massive thrombosis of left atrium (LA). Hospital lethality while the mitral valve prosthesis (including those in combination with correction of a three-cuspid valve) have constituted 6.1%, after open mitral comissurotomy all the patients are alive. Small cavity of a left ventricle, systolic pressure in pulmonary artery over 90 mm Hg, previously performed closed mitral comissurotomy, left atriomegaly, calcinosis of a mitral valve +3 have constituted factors of risk on a hospital stage. Important element to correct is excision of a base-lining and ligation of a LA eyelet, what essentially lowers the hospital lethality risk, rate of thromboembolic complications on a hospital stage.


Assuntos
Implante de Prótese de Valva Cardíaca/métodos , Estenose da Valva Mitral/cirurgia , Trombose/cirurgia , Adulto , Idoso , Feminino , Átrios do Coração/cirurgia , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/mortalidade , Trombectomia/métodos , Trombectomia/mortalidade , Trombose/complicações , Trombose/mortalidade , Resultado do Tratamento , Adulto Jovem
13.
Klin Khir ; (6): 34-6, 2014 Jun.
Artigo em Russo | MEDLINE | ID: mdl-25252550

RESUMO

The aortal valve prosthesis in combination with a tape-like bandage of ascending aorta application was performed in 106 patients, suffering a failure with predominance of the aortal valve stenosis in conjunction with the ascending aorta poststenotic dilation, in a 2005 - 2014 yrs period in the clinic. The hospital lethality have constituted 0.9%. In accordance to echocardiography, the ascending aorta diameter preoperatively have constituted (48.7 +/- 1.4) mm at average, before discharge from the hospital--(40.1 +/- 1.2) mm, in late follow-up period--(41.3 +/- 1.2) mm. It is expedient to recommend the original method of a tape-like bandage of ascending aorta from the base of noncoronary sinus in the aortal sinuses dilation (45 mm and more) in combination with the aortal valve prosthesis in poststenotic dilation of ascending aorta.


Assuntos
Aorta/cirurgia , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Técnicas de Sutura , Adulto , Idoso , Aorta/diagnóstico por imagem , Aorta/patologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/patologia , Bandagens , Prótese Vascular , Implante de Prótese Vascular/instrumentação , Dilatação Patológica , Circulação Extracorpórea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
14.
Klin Khir ; (8): 39-41, 2014 Aug.
Artigo em Russo | MEDLINE | ID: mdl-25417286

RESUMO

Possibilities of the procedures conduction of the left atrium (LA) plasty in a mitral valve prosthesis (MVP) were studied. There were examined 553 patients, in whom surgical treatment in the clinic was conducted. In all the patients MVP was conducted for isolated mitral valve failure and dilatation of LA. In 371 patients (the main group) MVP and LA plasty were conducted, in 182 (control group)--LA was not corrected. Morphometric indices of left cardiac cameras, survival, stability of the operation good results in late terms have witnessed high efficiency of MVP with LA reduction in comparison with such in a control group. Late results of MVP in conjunction with LA reduction exceed such in a control group, witnessing expediency of the proposed methods of surgical treatment application.


Assuntos
Anuloplastia da Valva Cardíaca/métodos , Átrios do Coração/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Função do Átrio Esquerdo/fisiologia , Feminino , Átrios do Coração/fisiopatologia , Próteses Valvulares Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/fisiopatologia , Índice de Gravidade de Doença , Resultado do Tratamento
15.
Klin Khir ; (9): 39-40, 2014 Sep.
Artigo em Russo | MEDLINE | ID: mdl-25509432

RESUMO

Possibilities of application of the proposed procedure for intraoperative restoration of the sinus rhythm while the mitral valve prosthesis (MVP) were studied up. In 161 patients, suffering the isolated mitral valve failure stage IV, a surgical treatment was conducted in Department of surgical treatment of acquired heart failures. The left atrium plasty was conducted in 119 (73.9%) of them with the objective to reduce its size and eliminate the re-entry waves passability. Fragmentation in left atrium was conducted in lowradiofrequency regime of diathermy (25-35 W) in accordance to variant (cut and sew) of operations Maze - 3 and Maze - 4. On a hospital stage 3 patients died (hospital lethality 1.9%). MVP in combination with Maze operation in a lowradiofrequency regime have permitted to restore successfully a correct rhythm in 80.2% of patients on a hospital stage and to stabilize it during 1 year postoperatively.


Assuntos
Fibrilação Atrial/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Anuloplastia da Valva Mitral/métodos , Insuficiência da Valva Mitral/cirurgia , Adulto , Idoso , Fibrilação Atrial/etiologia , Função do Átrio Esquerdo/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Próteses Valvulares Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/fisiopatologia , Resultado do Tratamento
16.
Sci Rep ; 14(1): 7546, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555301

RESUMO

The excitation of terahertz plasmon modes in a graphene rectangle by normally incident linearly polarized electromagnetic wave has been theoretically studied. The complete electromagnetic approach based on formulation of the integral equations for sought-for electromagnetic quantities has been developed. The influence of edge-field effects on excitation of plasmon modes for different polarization of the incident wave and different shapes of graphene rectangle has been studied. The absorption cross-section spectra and the charge density distributions in graphene rectangle for different plasmon modes have been studied. It has been found that the edge-field effect, which results in spreading the plasmon field beyond the geometric boundaries of graphene rectangle, leads to considerable red shifts of the plasmon mode frequencies and modifies the plasmon mode dispersion.

18.
J Phys Condens Matter ; 35(25)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36963112

RESUMO

We study for the first time the interaction between the waveguide modes of graphene structure and freely propagating terahertz (THz) electromagnetic waves (this interaction takes place within the light cone). We revealed a new and rather unexpected physical phenomenon by showing that freely incident THz electromagnetic waves can resonate with the surface transverse electric (TE) modes of the graphene waveguide in virtue of these modes having their dispersions in the vicinity of the light cone. The dispersion and amplification of surface TE modes in a dielectric waveguide covered with two graphene layers biased by direct current (DC), as well the amplification and lasing of incident THz wave by excitation of TE mode resonances, are investigated. The DC flows perpendicular to the direction of the surface wave propagation and creates the capacitive complex conductivity of graphene at THz frequencies, which is necessary for the existence of surface TE modes in graphene. The real part of graphene conductivity can be negative at THz frequencies due to DC in graphene which leads to amplification and lasing of THz radiation. Such structure can be of great practical importance because an external THz wave can be amplified or generated in lasing process without using special coupling elements commonly needed for ensuring the interaction between external THz wave and surface waveguide modes. The use of a two-layer graphene structure makes it possible to reduce the charge-carrier drift velocity required for reaching the lasing threshold at those resonances, as compared to a structure with a single graphene layer.

19.
J Nanosci Nanotechnol ; 12(9): 7562-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23035517

RESUMO

A mechanism of unidirectional exchange anisotropy formation at thermo-magnetic treatment of permalloy-manganese bilayers has been studied. A shift of hysteresis loops appears at annealing beginning from 230 degrees C. The maximal exchange field of 155 Oe is reached after the 250 degrees C annealing for 2 h. As demonstrated by transmission electron microscopy, the exchange bias and the coercivity growth result from an ordered anti-ferromagnetic NiFeMn phase formation due to the diffusion interaction of permalloy and manganese at annealing.

20.
Aviakosm Ekolog Med ; 46(3): 64-7, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23074954

RESUMO

Incidence of symptoms and clinical signs of chronic cardiac insufficiency (CCI) was studied in sailors in the Northern basin. Their variations were tracked and risk factors of that are most likely to provoke cardiovascuar diseases (CVDs) during 6-mos. voyages were elicted. Examined were 225 sailors of 10 sister large-capacity vessels belonging to Russian shipowners. Clinical condition and the cardiovascular function of the sailors were assessed on months 1, 3 and 6 using physical methods and ECG, provocative tests and clinical condition scoring scale. Physical activity was evaluated. Incidence of CCI symptoms and clinical signs in sailors was significantly in excess of the all-Russian value. Clinical condition of sailors with CCI symptoms and clinical signs was noted to grow worse by the end of voyage. Factors contributing to CCI development and aggravation during long voyages were identified.


Assuntos
Cardiopatias/fisiopatologia , Coração/fisiopatologia , Adulto , Idoso , Alcoolismo , Pressão Sanguínea , Doença Crônica , Eletrocardiografia , Cardiopatias/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Militares , Medicina Naval , Sobrepeso , Exame Físico , Fatores de Risco , Federação Russa , Índice de Gravidade de Doença , Fumar , Fatores de Tempo
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